(a) Field of the Invention
This application relates to an anti-siphon valve system, and more particularly for a system that facilitates winterization of the valve system and which includes an improved anti-siphon valve system.
(b) Discussion of Known Art
Anti-siphon valves are widely used with irrigation systems. A popular anti-siphon valve is used as part of FEBCO Series 765 Pressure Vacuum Breakers. These anti-siphon devices are discussed in my U.S. Pat. No. 7,934,515, (“the '515 patent”) issued May 3, 2011, and which is incorporated herein by reference in its entirety.
While the arrangements discussed in my '515 patent perform as expected, these devices are designed for service by trained technicians or experienced personnel. Additionally, these devices are widely used as part of home sprinkler or irrigation systems, which means that a technician must visit the residence where the system is installed and properly “winterize” the system in areas where freezing is likely to occur during the winter months. This winterization involves the removal of water from the entire sprinkler system, including the anti-siphon valves used with the system. Winterization is typically carried out with the use aid of a large-capacity air compressor that is used to blow out water that is found in the irrigation system after the main water line to the irrigation system has been closed.
However, it often happens that sudden cold fronts strike very quickly in fall and spring months, which results in an immediate need for winterization of a very large number of irrigation systems in hopes of avoiding freezing of water trapped in the irrigation system. This sudden need for assistance from trained technicians outstrips the supply of available technicians, and results in failed attempts at “do-it-yourself” winterizing by homeowners. The result is that water that is trapped in the irrigation system freezes and causes serious damage to components of the irrigation system.
One of the components that commonly damaged by freezing before winterization is the anti-siphon valve, which is often referred to as the “anti-backflow” device. Municipalities almost always require the installation of anti-siphon devices as part of irrigation systems. The function of the anti-siphon device is to allow air into the system once water pressure is turned off from the house or other building connected the municipal water system. Allowing air into the system results in draining of much of the water from the system, and ensures that a siphon is not created between the municipal water system and the irrigation system.
Homeowners can typically locate and shut off the main water valve to their irrigation system, but are often unable to drain water that remains in the backflow devices that are part of the irrigation system. Similarly, homeowners may not have the equipment needed to thoroughly remove potentially harmful levels of water that may remain trapped in valves, and particularly in ball valves that are commonly used in irrigation systems. As a consequence of the inadequate drainage, the backflow devices are then damaged or destroyed by the expansion of freezing water trapped in the devices.
Therefore there remains a need for a simple device that allows homeowners to quickly and easily drain water from major components of an irrigation system without the need of a high-capacity air compressor, or special tools and skills.
Additionally, there remains a need for a simplified anti-backflow installation system that can be quickly drained of water with a few common hand tools, such as with a screwdriver and an adjustable spanner.
Still further, there remains a need for a simplified bonnet and lower poppet valve arrangement that can be used with the body of well-known anti-backflow devices, such as the FEBCO Series 765 Pressure Vacuum Breakers. The simplified bonnet and lower poppet arrangement using fewer parts than are used with known devices, and allowing easier and less expensive repair of anti-backflow devices once they fail due to age or freezing.